Cold roll forming apparatus

ABSTRACT

A cold roll forming mill for the manufacture of hollow flange seam welded beams from a single strip of metal comprises a forming station ( 1 ), a seam guide and welding station ( 2 ) and a shaping station ( 3 ). Either or both of the forming and shaping stations ( 1,3 ) comprise independently supported side engaging roll combinations ( 7,12 ) adapted, in use, to roll either or both of opposite sides of the strip. Adjacent transverse pairs of side engaging roll ( 7,12 ) combinations are selectively movable relative to each other in a transverse direction perpendicular to a direction of travel of said strip through said mill. At least some of the side engaging roll combinations ( 7,12 ) are driven. Drive rolls ( 6 ) spaced within the forming and shaping stations ( 1,3 ) engage the strip between opposite edges thereof.

FIELD OF THE INVENTION

This invention is concerned with improvements in cold roll formingmills.

The invention is concerned particularly, although not exclusively, withaspects of a cold roll forming mill for hollow flange members.

More particularly, the invention is concerned with aspects of a coldroll forming mill for the continuous production of dual welded hollowflange beams.

BACKGROUND OF THE INVENTION

It is known to produce hollow flange members by cold forming light gaugesteel strip to form a section having a planar web and hollow triangularcross-section flanges extending along opposite sides of the web. U.S.Pat. Nos. 991,603 and 3,342,007 describe the manufacture of such beamsby a cold forming process wherein the free edge of the hollow flangelies adjacent the edge of the web but is not secured thereto. Thesehollow flanges are known as “open” flanges and lack torsionalresistance.

U.S. Pat. No. 3,698,224 describes the manufacture of hollow flange beamsby a cold forming process wherein seam welded steel tubing is subjectedto a shaping process which flattens the tube to form a hollow flangebeam with a pair of juxtaposed webs.

In order to improve the section efficiency of “open” flange beams, ithas been proposed to secure the edges of the hollow flanges to the webto improve torsional stiffness in the flanges. U.S. Pat. Nos. 6,436,552,6,115,986, 6,397,550 and 5,692,353 describe cold formed thin gaugehollow flange beams wherein a lip formed along the edge of the hollowflange is secured to the web intermediate its edges by fasteners, clinchperforations, spot welding or the like.

Russian Inventor's Certificate 827723 describes a cold formed thin gaugehollow flange beam wherein the free edges of the hollow flanges areformed as internally folded lips or formations to support the hollowflanges against localized crushing under load. A side wall of the hollowflange is welded by a fillet weld to the edge of the web to form a“closed” flange.

In order to reduce the costs of manufacture of cold formed “closed”hollow flange beams, an in-line dual welding process was devised anddescribed in U.S. Pat. No. 5,163,225, in respect of which, the assigneeof the present invention is the successor in title. The dual weldingprocess described for the first time an in-line high frequency inductionor resistance welding process wherein a free edge of a hollow flange waswelded to the face of the strip of metal to form a weld seam adjacentthe edge of the web of the hollow flange beam so formed. In thatprocess, a conventional tube rolling mill was adapted to produce hollowflange beams having circular cross-section flanges at the weld station,the circular cross-section flanges subsequently being shaped totriangular cross-section to form “Dogbone” (Registered Trade Mark)beams.

While generally satisfactory for a relatively narrow range of web andflange widths and a narrow range of metal strip gauges, an adaptation toa conventional mill structure was considered to be not only limiting inthe scope of beam sizes but also inefficient and capital intensive interms of requiring a large number of roll sets of large diameter whichcaused considerable unproductive downtime each time a roll change wasrequired for a different beam size. Moreover, difficulties inmaintaining weld seam stability imposed severe limitations on yield dueto a high reject rate.

One proposal to address some of the shortcomings in the original“Dogbone” process was described in U.S. Pat. No. 5,403,986. Thisdocument proposed a tandem mill structure with separate spaced coldforming mills inclined to a longitudinal axis in a forming section ofthe mill. Shaped flanges, independently produced from separate strips ofmetal were brought together with a third planar web strip such that theedges of the web protruded between the free edges of the flanges priorto welding. The welding and forming stations were substantially the sameas those described in U.S. Pat. No. 5,163,225.

As used herein, the expression “ERW” refers to electrical resistance orinduction welding using either contacts or induction coils/impeders tocreate a current in the member and other forms of electrical resistancewelding.

It is an aim of the present invention to overcome or alleviate at leastsome of the disadvantages of prior art methods and apparatus for theproduction of hollow flange seam welded beams.

SUMMARY OF THE INVENTION

According to one aspect of the invention there is provided a cold rollforming mill for the manufacture of hollow flange seam welded beams froma single strip of metal, said mill comprising:

a forming station;

a seam guide and welding station; and,

a shaping station, said mill characterized in that either or both ofsaid forming station and said shaping station comprises independentlysupported side engaging roll combinations adapted, in use, to rollopposite sides of said strip, adjacent transverse pairs of said sideengaging roll combinations being selectively movable relative to eachother in a transverse direction perpendicular to a direction of travelof said strip.

Suitably, some or all of said side engaging roll combinations are idlerrolls.

If required, some or all of said side engaging roll combinations aredrive rolls.

Preferably, drive rolls, spaced within said forming station and spacedwithin said shaping station engage a central region of said stripbetween formed edges thereof.

If required, some or all of said drive rolls may engage said strip overa substantial portion thereof between formed edges of said strip.

Alternatively, some or all of said drive rolls may engage said stripadjacent a central portion spaced from said formed edges.

In a still further alternative, some or all of said drive rolls mayengage said strip adjacent opposed formed edges thereof.

The transverse pairs of side engaging roll combinations may be mountedon respective roll stand frames.

If required, transverse pairs of said side engaging roll combinationsmay be movably mounted on a common roll stand frame.

Suitably, said roll stand frames are selectively movable transversely ofa mill bed.

The transverse pairs of side engaging roll combinations may be alignedin a transverse plane perpendicular to a direction of travel of a stripof metal between said side engaging roll combinations.

Preferably, each of said transverse pair of side engaging rollcombinations is located in a respective longitudinally spaced transverseplane perpendicular to a direction of travel of a strip of metal betweensaid side engaging roll combinations.

If required, at least one of a side engaging roll of a side engagingroll combination is rotatably mounted on an inclined axis lying in atransverse plane perpendicular to a direction of travel of a strip ofmetal through said side engaging roll combination.

At least one side engaging roll of a side engaging roll combination maybe rotatably mounted on a horizontal axis lying in a transverse planeperpendicular to a direction of travel of a strip of metal through saidside engaging roll combination.

Suitably, at least one side engaging roll of a side engaging rollcombination is rotatably mounted on a vertical axis.

If required, said drive rolls may alternate with said side engaging rollcombinations along a mill bed.

Suitably, any or all of said at least one of a side engaging roll of aside engaging roll combination is rotatable on an axis selectivelyangularly adjustable in a plane lying perpendicular to a direction oftravel of a metal strip in said mill.

Preferably, said drive rolls are located between pairs of longitudinallyspaced side engaging roll combinations along said mill bed.

Suitably, said seam guide and welding station includes a seam guide rollstand having at least one seam guide roll having a circumferentialshoulder pivotally mounted on an inclined rotational axis lying in atransverse plane perpendicular to a direction of travel of said strip.

If required, said at least one seam guide roll may be selectivelymovable along said inclined axis.

The rotational axis of said seam guide roll may be selectively angularlyadjustable in said transverse plane.

Preferably, the seam guide and welding station includes a weld box standhaving at least one squeeze roll pivotally mounted on an inclinedrotational axis lying in a transverse plane perpendicular to a directionof travel of said strip.

Suitably, said at least one squeeze roll may be selectively movablealong said inclined axis.

If required, the rotational axis of said at least one squeeze roll maybe selectively angularly adjustable in said transverse plane.

Preferably, one or more of said forming rolls and/or said shaping rollsmay be rotatably journalled in a mounting frame releasably securable toa respective forming roll stand and/or a shaping roll stand.

If required, one or more sets of said forming rolls and/or said shapingrolls may be rotatably journalled in a mounting frame releasablysecurable to a respective forming roll stand and/or a shaping rollstand.

Suitably, said mounting frame is adjustable in a transverse planeperpendicular to a direction of travel of said strip through saidmounting frame.

Preferably, said seam guide and welding station comprises:

a seam roll stand rotatably supporting at least one seam roll adapted,in use, to guide a free edge of a contoured edge region of said metalstrip into linear alignment with a predetermined weld axis spaced fromsaid free edge on a surface of said metal strip; and,

a weld box stand rotatably supporting at least one pair of squeezerolls, in use, to urge said free edge when heated to a predeterminedtemperature into fused engagement with a correspondingly heated saidweld axis on said surface, said pair of squeeze rolls co-operating, inuse, to guide said free edge through a predetermined linear trajectorysubstantially along an incidence axis of a subsequent weld junctionbetween said free edge and said surface of said metal strip wherebyenergy imparted to said cold formed member is focussed by a proximityeffect along said predetermined weld axis of said surface.

Suitably, said electrical current is induced in said free edge and saidweld region by electrical contactors slidably engaging said metal stripadjacent said free edge and said weld region.

Preferably, said electrical current is induced in said free edge andsaid weld region by an induction coil transversely surrounding saidmetal strip in a plane perpendicular to a direction of travel of saidmetal strip therethrough.

Preferably, at least one of said pair of squeeze rolls is angularlyadjustable in a plane perpendicular to a direction of travel of saidmetal strip therebetween.

At least one of said pair of squeeze rolls may be adjustable relative tothe other of said pair in a direction perpendicular to a rotational axisof said at least one of said pair of squeeze rolls.

Suitably, said weld box includes web support rolls rotatable aboutparallel respective axes perpendicular to a direction of travel of ametal strip member therebetween.

If required, a web support roll may have a contoured outer edge tofunction as one of said pair of squeeze rolls.

The apparatus may include more than one seam roll stand.

If required, at least one of said seam roll stands includes a seam rollhaving a circumferential shoulder thereon, said circumferentialshoulder, in use, providing an abutment for said free edge of said metalstrip.

Suitably, a contoured guide roll is provided, in use, to urge said freeedge of said metal strip into abutment with said circumferentialshoulder.

If required, a rod-shaped impeder supported at one end thereof, upstreamof said one or more seam roll stands, extends into a hollow interior ofa contoured edge region of said metal strip.

According to another aspect of the invention there is provided a methodof cold roll forming a hollow flange member from a single strip ofmetal, said method comprising the steps of:

driving a metal strip through a cold rolling mill by driven rollsengaging a planar central region of said strip;

forming a contour along at least one edge region of said strip byforming rolls;

continuously seam welding by an ERW process a free edge of said at leastone edge region to a surface of said strip along a predetermined weldregion to form a hollow flange; and,

shaping said hollow flange by shaping rolls to form a shaped hollowflange of desired cross-sectional configuration.

If required, one or more of said forming rolls may be driven.

In addition, or alternatively, one or more of said shaping rolls may bedriven.

Suitably, forming of said hollow flange is effected by one or moreforming rolls rotatably supported about a pivotal axis inclined at anangle between vertical and horizontal in a transverse planeperpendicular to a direction of travel of said strip of metal.

If required, shaping may be effected by one or more shaping rollsrotatably supported about a pivotal axis inclined at an angle betweenvertical and horizontal in a transverse plane perpendicular to adirection of travel of said strip of metal.

Forming of said hollow flange may be effected by forming rolls mountedin longitudinally spaced transverse operating planes, said spacedoperating planes being parallel to each other and perpendicular to adirection of travel of said strip of metal.

Suitably, shaping of said hollow flange may be effected by shaping rollsmounted in longitudinally spaced transverse operating planes, saidspaced operating planes being parallel to each other and perpendicularto a direction of travel of said strip of metal.

Preferably prior to said step of continuous seam welding, said free edgeis aligned linearly with a predetermined weld axis on said surface ofsaid strip and said at least one free edge is guided through apredetermined linear trajectory along an incidence axis of a subsequentweld junction between said at least free one free edge and said surfacewhereby energy imparted to said hollow flange member is focussed by aproximity effect along said predetermined weld axis on said surfaceprior to fusing said at least one free edge thereto.

If required, said at least one free edge is aligned with said weldregion by one or more seam rolls each having a circumferential shoulderproviding an abutment for said at least one free edge.

Said at least one free edge of said metal strip may be urged intoabutment with said circumferential shoulder by a contoured guide roll.

Suitably, said metal strip is supported centrally by opposed cylindricalroll surfaces adjacent said weld region as said at least one free edgeis urged into abutment with said circumferential shoulder.

Said at least one free edge may be guided toward said closure region ata predetermined angle relative to strip surface by adjustably mountedseam rolls.

Preferably, said at least one free edge of said metal strip is guidedthrough said predetermined trajectory by a contoured squeeze rollextending over said contoured surface of said metal strip between spacedsubstantially parallel contact faces of said contoured squeeze roll.

Weld energy may be imparted to said free edge and said predeterminedweld region by an electrical induction coil or contactors, said coilextending substantially around said metal strip in a plane substantiallyperpendicular to a longitudinal axis thereof.

If required, an elongate rod-like induction impeder supported at one endmay extend within a hollow interior cavity of said contoured surface toa region adjacent a closure region where said at least one free edge isfused to said surface of said metal strip.

BRIEF DESCRIPTION OF THE DRAWINGS

In order that the various aspects of the invention may be more fullyunderstood and put into practical effect, reference will now be made topreferred embodiments illustrated in the accompanying drawings in which:

FIG. 1 is a schematic side elevational view of a forming station andedge preparation and welding station of a cold roll forming mill;

FIG. 2 is a schematic side elevational view of a shaping station of acold roll forming mill;

FIG. 3 shows schematically a front elevation of a driven roll standfitted with side rolls;

FIG. 4 shows schematically a rear elevation of a forming roll stand;

FIG. 5 shows schematically a rear elevation of a seam guide roll stand;

FIG. 6 shows schematically a side elevation of a welding apparatus;

FIG. 7 shows schematically a front elevation of a weld box stand;

FIG. 8 shows schematically the operation of the squeeze rolls in theweld box stand;

FIG. 9 shows schematically front, side and rear elevations of a shapingroll stand;

FIG. 10 shows schematically side and front elevations of a turk's headroll stand.

As used herein, the expression “front elevation” means a view in thedirection of travel of a strip of metal therethrough.

Moreover, like numerals are employed for like features in the drawingsfor the sake of clarity.

DETAILED DESCRIPTION OF THE DRAWINGS

In FIGS. 1 and 2, the cold forming mill comprises a forming station 1,an edge preparation and welding station 2 and a shaping station 3.Conventional slit strip roll handling and let off rolls upstream of theforming station 1 and flying saw and take-off table assemblies at thedownstream end of shaping station 3 are omitted for the sake of clarity.

In FIG. 1, mill beds 4 support a conventional entry table 5, a series ofdrive roll stands 6, a series of forming roll stands 7, side rollassemblies 8, a seam guide roll stand 9, a weld coil 10 and a weld box11.

FIG. 2 shows a downstream portion of the cold forming mill wherein millbeds 4 support drive roll stands 6, shaping roll stands 12 and a turk'shead roll stand 13.

FIG. 3 shows a front elevational view of drive roll stand 6 a of FIG. 1.This roll stand differs from other roll stands 6 only in that itincludes side rolls to steady the formed strip prior to entry into theseam guide roll stand 9.

Drive roll stand 6 a comprises a pair of spaced frames 20 in which arejournalled roll shafts 21, each supporting a respective cylindricaldrive roll 22. Roll shafts 21 are coupled via universal joints 23 todrive shafts 24 coupled to a conventional drive train (not shown). Ascan be seen, drive rolls 22 engage the central web 25 of a formed hollowflange beam member 26 and because the grip on the web is so good, it hasbeen found unnecessary to drive any of the forming or shaping rolls inthe mill. A conventional height adjustment mechanism 27 providesvertical height adjustment to upper roll shaft 21 to adjust the nipbetween upper and lower rolls 22 to accommodate differing metal stripfeedstock thickness. If required, selected drive rolls may be contouredto assist in forming or shaping hollow flanges.

Mounted on an upstream side of roll stand 6 a is a side roll assemblycomprising a pair of side rolls 28 supported on respective mountingbrackets 29. Side rolls 28 engage the hollow flanges 30 of member 26 forprecise lateral location prior to entry into the seam guide roll stand 9and are adapted for lateral adjustment by screw adjuster 31 and forvertical adjustment by screw adjusters 32.

FIG. 4 illustrates a rear elevational view of a typical undriven formingroll stand 7 showing a pair of frames 35 adjustably mounted on a base 36for selective relative lateral movement by a shaft 37 having threadedportions 38,38 a of opposite hand engaging in respective slide blocks39,39 a. Frames 35 are slidably adjustable between inner and outer stops40,41 respectively.

Upper and lower forming rolls 42,43 are supported on respective mountingbrackets 44,45 and upper mounting brackets 44 are slidably mounted onframes for vertical adjustment by adjusting screws 46 to accommodatediffering thicknesses of the metal strip feedstock or differing roll setconfigurations.

FIG. 5 shows a rear elevational view of a seam guide roll stand 9 havinga base 50 and a support frame 51. On the downstream side of the frame asviewed are a pair of contoured support rolls 52 which support the hollowflange regions 30 on either side of web 25. Rolls 52 are rotatablyjournalled in lower roll support brackets 53 slidably mounted on frame51 and movable laterally relative to each other by an oppositely handedthreaded screw adjustment 54. Vertical adjustment of lower roll supportbrackets 53 is achieved by screw-threaded adjusters 55. Seam guide rolls56 are mounted on upper roll support brackets 57 which are mounted forlateral relative movement on frame 51 by adjuster 58 having a shaft 59with oppositely handed screw-threads and also for vertical movement byadjuster screws 60.

Seam guide rolls 56 have a circumferential shoulder 61 which provides anabutment against with the free edge 62 of hollow flange 30 is urged.Seam guide rolls rotatably journalled in slide blocks 63 which arelinearly adjustable along respective rotational axes 64 by adjusterscrews 65 and, if required slide blocks 63 may be pivotally mounted onupper roll support brackets for angular adjustment in a transverse planeperpendicular to a direction of travel of the metal strip feedstocktherethrough.

Mounted on a front side of frame 51 is a pair of web support rolls66,67, upper support roll 66 having a circumferential rim 68 engagingbetween the free edge 62 of the flange 30 and the side of web 25 asshown in the cutaway region 69. The end wall 70 of support roll 66 alsoserves as an abutment for free edge 62 of flange 30. Also shown incutaway region 69 is a contoured end wall 71 of lower support roll 67which also supports the hollow flange 30. Relative vertical movementbetween web support rolls 66 and 67 is achieved by adjuster screw 72.

FIG. 6 shows a high frequency electrical induction welding apparatus 10shown schematically in FIG. 1 between seam guide roll stand 9 and weldbox 11.

Welding apparatus 10 comprises an induction coil assembly 75 in the formof a sheet copper loop 76 which surrounds a hollow flange member 77 asit passes therethrough. Loop 76 is supported at its free ends 78 byrespective sheet copper support brackets 79 separated by an electricalinsulating medium 80. Coil assembly 75 is cooled by water recirculatingin copper tubes 81 secured to assembly 75.

Located within each hollow flange 30 in the region of coil 76 is animpedance device 82 comprising a fibreglass tube filled with ferriterods (not shown). Each impeder 82 is supported by an elongate rod 83supported by a bracket 84 (shown in FIG. 1) which extends into thehollow interior of a respective web via the gap between the free edge ofthe hollow flange and the side of the web as seen in FIG. 5. Coolingwater is recirculated through the impeder 82 via tubes 85 and a sourceof compressed air is pumped through the impeder 82 via tube 86. Afterthe free edges of the hollow flanges and the weld seam lines along therespective sides of the web are heated to fusion temperature by thewelding apparatus 10, the heated free edges of the flanges are urgedinto contact with respective heated weld seam lines by squeeze rollsets, shown schematically at 87, in the weld box 11 of FIG. 1.

FIG. 7 shows the configuration of the four roll weld box 11 in FIG. 1.

Weld box 11 comprises a cylindrical top roll 90 and a cylindrical lowerroll 91 with contoured edges 91 a, each of rolls 90,91 being rotatablyjournalled about respective rotational axes 92,93. Contoured squeezerolls 94 a,94 b rotatable about respective inclined axes 95 a,95 b areadapted to urge the heated free edges 62 a,62 b of hollow flanges 30into respective heated weld seam line regions along the opposedboundaries of web 25 to effect fusion therebetween to create acontinuous weld seam. It will be noted that the cavities defined betweensqueeze rolls 94 a,94 b and respective contoured edges 91 a ofcylindrical support roll 91 are ovoid in shape.

The free edges 62 a,62 b are urged toward respective weld lines in alinear fashion perpendicular to the respective rotational axes 95 a,95 bof squeeze rolls 94 a,94 b without a transverse “sweeping” actionthereby maintaining stable induction “shadows” or pathways on or at thedesired position of the weld seams between respective free edges 64 a,64b and the opposed boundaries of web 25.

Cylindrical roller 90 is adjustably mounted for movement in an uprightplane by adjustment screw 96, the screw 96 being coupled to rollcarriage 98, slidably mounted in support frame 100.

Squeeze rolls 94 a,94 b are slidably mounted in respective carriages101,102 of squeeze roll support frames 103,104 respectively for slidableadjustment along respective sliding axes 105,106 means of adjustmentscrews 107. Squeeze roll support frames 103,104 are, in turn, adjustablymounted for transverse movement by a screw 108 coupling mountings forsupport frames 103,104 by a threaded shaft 109 and for upright movementby screws 110. Preferably, roll support frames are pivotally mounted onframe 100 for pivotal movement about respective axes parallel to thedirection of movement of a hollow flanged member moving through weld boxstand 11.

The adjustable roll mounting enables a wide range of hollow flangemembers of varying dimensions and cross-sectional configurations to bewelded in the weld box with extremely precise control over thetrajectory through which the free edges of the hollow flanges traveltowards a precisely located weld seam line adjacent or at the edges ofthe member web.

FIG. 8 shows schematically the configuration of the rolls in weld box 11of FIG. 7 to more clearly illustrate the guidance of the free edges ofthe hollow flanges into the weld seams along the edges of the web.

In the drawing a somewhat exaggerated position of the formed hollowflanges 30 and their respective free edges 62 is shown in phantom. Asthe formed section approaches the roll combination, hollow flanges 30are urged inwardly towards the contoured ends 91 a of separate rollers91 which correspond to the movement of rollers 94 a,94 b alongrespective sliding axes 105,106 as shown in FIG. 7.

Importantly, it can be seen that about half of the outer portion of thehollow flanges which terminate in the free edges 62 is urged in thedirection shown by arrows 111 whereby the almost flat region of theflange adjacent the free edge 62 and a corresponding portion of theopposite side of the flange are driven together as a unitary portiontowards roll 91 whereby deformation of the remaining portion of theflange adjacent the boundary 79 of the web 25 is accommodated in thecontoured edges 91 a of rolls 91. Equally, it will be seen that the freeedge 62 of the flange 30 travels in a straight line trajectory to theboundary 79 of web 25 where the weld seam is formed.

FIG. 9 shows a shaping roll stand 12 of FIG. 2 wherein FIG. 9 a is arear elevational view, FIG. 9 b is a side elevation and FIG. 9 c is afront elevational view.

Roll stand 12 comprises an arched plate-like frame 120 reinforced by aweb 121 attached about an outer edge thereof. Frame 120 is supported onbase pads 122 and includes lifting eyes 123 for ease of handling. Trackmembers 124,125 slidably locate a shaping roll carriage 126 which istransversely adjustable by adjuster screw 127. Mounted about a centralaperture 128 in frame 120 are shaping roll support frames 129, eachslidably locating a roll mounting bracket 130 in which is rotatablyjournalled a shaping roll 131. Roll mounting brackets 130 are slidablyadjustable in respective support frames 129 by adjuster screws 132 whichmove the shaping rolls 131 in a transverse plane perpendicular to thedirection of travel of a hollow flange 133 a of a beam 133 movingtherethrough. Shaping rolls 131 are mounted with respective rotationalaxes in a common transverse mounting plane represented at 134 in FIG. 9b and respective adjuster screws 127 move the shaping rolls 131 in theircommon mounting plane in a direction perpendicular to respectiverotational axes.

Just visible via aperture 128 is a set of three shaping rolls 131 aengaged about an opposite hollow flange 133 b of beam 133 on the otherside of frame 120.

As can be seen from FIGS. 9 b and 9 c a front elevational view of theshaping roll stand is substantially identical except that roll carriage126 is displaced to the left to accommodate hollow flange 133 b spacedfrom hollow flange 133 a by the width of the web therebetween.

Although like reference numerals have been employed for like features,the reference numerals for the features on the front face aredistinguished by a prime.

The particular advantages conferred by this configuration of roll stand,whether for shaping rolls or forming rolls is its adaptability to a widerange of sizes of hollow flanged beams with a wide range ofcross-sectional shapes possible in the hollow flanges. Moreover,location of the roll sets for opposite flanges in longitudinally spacedplanes permits the ruse of multiple roll combinations such as thatillustrated without the interference with an adjacent set of rolls inthe same plane for shaping or forming of an opposite hollow flange. Byusing a three roll set of forming rolls as shown hollow flange beamswith closely spaced or otherwise relatively deep flanges can now berolled without the limitations otherwise imposed in conventional mills.

A still further advantage of a roll stand as illustrated in FIG. 9 witha three roll shaping set is that by operating one of the rolls with aninclined rotational axis as shown, a tapered edge roll of a relativelysmall diameter can still provide a deep support face for an uprightflange edge without “scrubbing” the face of the flange as a result ofthe forming velocity differential across a planar side wall of acylindrical roll.

The roll stand shown in FIG. 9 is considered to permit substantial costsavings in the cost of roll sets as diameters of 25-30% less thanconventional roll diameters may be employed. Moreover, the adjustabilityof the rolls allows a large range of beam sizes can be rolled withouthaving to effect roll changes simply to accommodate changes in webwidth. Where roll changes are required either for a change in hollowflange beam size or configuration or merely for maintenance purposes, acomplete roll carriage changeover may be effected in minutes andsimilarly replacement of a mounting roll bracket also can be effectedrapidly.

FIG. 10 shows a double sided turk's head roll stand 13 having aconfiguration similar to shaping roll stands 12 shown in FIG. 9.

Referring in particular to FIG. 10 b, turk's head roll stand 13comprises a plate-like frame 140 with top and side reinforcing webs141,142 respectively. A mounting base 143 is adapted for mounting on amill bed as shown in FIG. 2 and lifting eyes 144 are provided forhandling purposes. Mounted on opposite faces of frame 140 are rollmounting plates 145 with aligned central apertures 146. Mounted aboutapertures 146 are roll mounting frames 147 slidably locating rollmounting brackets 148 which are axially adjustable by respectiveadjuster screws 149. Roll mounting plates 145 are axially adjustable byadjusting screws 150.

Roll mounting frames 147 are mounted on a face plate 151 in turnrotatably mounted on roll mounting plates 145 and at least partialrotation of face plate 151 relative thereto is effected by adjustingscrew 152. Relative rotational adjustment between the face plates 151 onthe front and rear sides of the turk's head frame 140 permits anytwisting or axial deformations in the hollow flange beam to be removedby idler rolls 153,154,155 and 156 before the beam progresses to aflying saw or the like to be severed into predetermined lengths.

It readily will be apparent to persons skilled in the art that manymodifications and variations may be made to the various aspects of theinvention without departing from the spirit and scope thereof.

1. A cold roll forming mill for the manufacture of hollow flange seamwelded beams from a single strip of metal, said mill comprising: aforming station; a seam guide and welding station; and, a shapingstation; wherein either or both of said forming station and said shapingstation comprises independently supported side engaging rollcombinations adapted, in use, to roll either or both of opposite sidesof said strip, adjacent transverse pairs of said side engaging rollcombinations being selectively movable relative to each other in atransverse direction perpendicular to a direction of travel of saidstrip through said mill, and all forming and shaping rolls of either orboth of said forming station and said shaping station consist of saidside engaging roll combinations; and wherein each of said roll standframes is independently and selectively movable transversely of a millbed.
 2. A mill as claimed in claim 1 wherein some or all of said sideengaging roll combinations are idler rolls.
 3. A mill as claimed inclaim 1 wherein some or all of said side engaging roll combinations aredrive rolls.
 4. A mill as claimed in claim 1 wherein drive rolls, spacedwithin said forming station and spaced within said shaping stationengage a central region of said strip between formed edge regionsthereof.
 5. A mill as claimed in claim 4 wherein some or all of saiddrive rolls engage said strip over a substantial portion thereof betweenformed edge regions of said strip.
 6. A mill as claimed in claim 4wherein some or all of said drive rolls engage said strip adjacent acentral portion spaced from said formed edges.
 7. A mill as claimed inclaim 4 wherein some or all of said drive rolls engage said stripadjacent opposed formed edges thereof.
 8. A mill as claimed in claim 1wherein transverse pairs of side engaging roll combinations are mountedon respective roll stand frames.
 9. A mill as claimed in claim 1 whereintransverse pairs of said side engaging roll combinations are movablymounted on a common roll stand frame.
 10. A mill as claimed in claim 1wherein at least one side engaging roll of a side engaging rollcombination is rotatably mounted on an inclined axis lying in atransverse plane perpendicular to a direction of travel of a strip ofmetal through said side engaging roll combination.
 11. A method of coldroll forming a hollow flange member from a single strip of metal, saidmethod comprising: driving a metal strip through a cold rolling mill bydriven rolls engaging a planar central region of said strip; forming acontour along at least one edge region of said strip by forming rolls;continuously seam welding by an ERW process a free edge of said at leastone edge region to a surface of said strip along a predetermined weldregion to form a hollow flange; and, shaping said hollow flange byshaping rolls to form a shaped hollow flange of desired cross-sectionalconfiguration; wherein said forming rolls and said shaping rolls consistof side engaging roll combinations each being independently andselectively movable relative to each other in a transverse directionperpendicular to a direction of travel of said strip through said mill.12. A method as claimed in claim 11 wherein one or more of said formingrolls are driven to assist in driving said strip through said mill. 13.A method as claimed in claim 11 wherein one or more of said shapingrolls are driven.
 14. A method as claimed in claim 11 wherein prior tocontinuous seam welding, said free edge is aligned linearly with apredetermined weld axis on said surface of said strip and said at leastone free edge is guided through a predetermined linear trajectory alongan incidence axis of a subsequent weld junction between said at leastfree one free edge and said surface wherein energy imparted to saidhollow flange member is focussed by a proximity effect along saidpredetermined weld axis on said surface prior to fusing said at leastone free edge thereto.
 15. A method as claimed in claim 11 wherein saidat least one free edge is aligned with said weld region by one or moreseam rolls each having a circumferential shoulder providing an abutmentfor said at least one free edge.
 16. A method as claimed in claim 15wherein at least one free edge of said metal strip is urged intoabutment with said circumferential shoulder by a contoured guide roll.17. A method as claimed in claim 15 wherein said metal strip issupported centrally by opposed cylindrical roll surfaces adjacent saidweld region as said at least one free edge is urged into abutment withsaid circumferential shoulder.
 18. A method as claimed in claim 15wherein at least one free edge is guided toward said closure region at apredetermined angle relative to strip surface by adjustably mounted seamrolls.
 19. A method as claimed in claim 11 wherein said at least onefree edge of said metal strip is guided through said predeterminedtrajectory by a contoured squeeze roll extending over said contouredsurface of said metal strip between spaced substantially parallelcontact faces of said contoured squeeze roll.
 20. A method as claimed inclaim 11 wherein weld energy is imparted to said free edge and saidpredetermined weld region by an electrical induction coil, said coilextending substantially around said metal strip in a plane substantiallyperpendicular to a longitudinal axis thereof.